2 * Copyright (c) 2013 Cisco Systems, Inc. and others. All rights reserved.
4 * This program and the accompanying materials are made available under the
5 * terms of the Eclipse Public License v1.0 which accompanies this distribution,
6 * and is available at http://www.eclipse.org/legal/epl-v10.html
8 package org.opendaylight.protocol.bgp.parser.impl.message.update;
10 import com.google.common.base.Preconditions;
11 import io.netty.buffer.ByteBuf;
12 import io.netty.buffer.Unpooled;
13 import java.util.ArrayList;
14 import java.util.Collections;
15 import java.util.List;
16 import org.opendaylight.protocol.bgp.parser.BGPDocumentedException;
17 import org.opendaylight.protocol.bgp.parser.BGPError;
18 import org.opendaylight.protocol.bgp.parser.BGPParsingException;
19 import org.opendaylight.protocol.bgp.parser.impl.message.update.AsPathSegmentParser.SegmentType;
20 import org.opendaylight.protocol.bgp.parser.spi.AttributeParser;
21 import org.opendaylight.protocol.bgp.parser.spi.AttributeSerializer;
22 import org.opendaylight.protocol.bgp.parser.spi.AttributeUtil;
23 import org.opendaylight.protocol.util.ReferenceCache;
24 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.inet.types.rev130715.AsNumber;
25 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.path.attributes.Attributes;
26 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.path.attributes.AttributesBuilder;
27 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.path.attributes.attributes.AsPath;
28 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.path.attributes.attributes.AsPathBuilder;
29 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.path.attributes.attributes.as.path.Segments;
30 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.path.attributes.attributes.as.path.SegmentsBuilder;
31 import org.opendaylight.yangtools.yang.binding.DataObject;
32 import org.slf4j.Logger;
33 import org.slf4j.LoggerFactory;
35 public final class AsPathAttributeParser implements AttributeParser, AttributeSerializer {
37 public static final int TYPE = 2;
39 private final ReferenceCache refCache;
40 private static final Logger LOG = LoggerFactory.getLogger(AsPathAttributeParser.class);
42 private static final AsPath EMPTY = new AsPathBuilder().setSegments(Collections.emptyList()).build();
44 public AsPathAttributeParser(final ReferenceCache refCache) {
45 this.refCache = Preconditions.checkNotNull(refCache);
49 * Parses AS_PATH from bytes.
51 * @param refCache ReferenceCache shared reference of object
52 * @param buffer bytes to be parsed
53 * @return new ASPath object
54 * @throws BGPDocumentedException if there is no AS_SEQUENCE present (mandatory)
55 * @throws BGPParsingException
57 private static AsPath parseAsPath(final ReferenceCache refCache, final ByteBuf buffer) throws BGPDocumentedException, BGPParsingException {
58 if (!buffer.isReadable()) {
61 final ArrayList<Segments> ases = new ArrayList<>();
62 boolean isSequence = false;
63 while (buffer.isReadable()) {
64 final int type = buffer.readUnsignedByte();
65 final SegmentType segmentType = AsPathSegmentParser.parseType(type);
66 if (segmentType == null) {
67 throw new BGPParsingException("AS Path segment type unknown : " + type);
69 final int count = buffer.readUnsignedByte();
71 final List<AsNumber> asList = AsPathSegmentParser.parseAsSegment(refCache, count, buffer.readSlice(count * AsPathSegmentParser.AS_NUMBER_LENGTH));
72 if (segmentType == SegmentType.AS_SEQUENCE) {
73 ases.add(new SegmentsBuilder().setAsSequence(asList).build());
76 ases.add(new SegmentsBuilder().setAsSet(asList).build());
80 throw new BGPDocumentedException("AS_SEQUENCE must be present in AS_PATH attribute.", BGPError.AS_PATH_MALFORMED);
84 return new AsPathBuilder().setSegments(ases).build();
88 public void parseAttribute(final ByteBuf buffer, final AttributesBuilder builder) throws BGPDocumentedException, BGPParsingException {
89 builder.setAsPath(parseAsPath(this.refCache, buffer));
93 public void serializeAttribute(final DataObject attribute, final ByteBuf byteAggregator) {
94 Preconditions.checkArgument(attribute instanceof Attributes, "Attribute parameter is not a PathAttribute object.");
95 final Attributes pathAttributes = (Attributes) attribute;
96 final AsPath asPath = pathAttributes.getAsPath();
100 final ByteBuf segmentsBuffer = Unpooled.buffer();
101 if (asPath.getSegments() != null) {
102 for (final Segments segments : asPath.getSegments()) {
103 if (segments.getAsSequence() != null) {
104 AsPathSegmentParser.serializeAsList(segments.getAsSequence(), SegmentType.AS_SEQUENCE, segmentsBuffer);
105 } else if (segments.getAsSet() != null) {
106 AsPathSegmentParser.serializeAsList(segments.getAsSet(), SegmentType.AS_SET, segmentsBuffer);
108 LOG.warn("Segment doesn't have AsSequence nor AsSet list.");
112 AttributeUtil.formatAttribute(AttributeUtil.TRANSITIVE, TYPE, segmentsBuffer, byteAggregator);